package j02final;

class Dog{
    final int age = 5;

    void f1(){
//        age = 6;
        System.out.println(Math.sqrt(4));//2
        System.out.println("Math.PI = " + Math.PI);
//        Math.PI = 7;
    }
}

public class J2final {
    public static void main(String[] args) {
//        new Dog().f1();

//        final int x1 = 6;
        final int x1;
        x1 = 88;
        //...
        //常亮，建议
        final int AGE = 55;
    }
}
